Correction and end-of-letter marker for dictating machine



July 11, 1961 w, ROBERTS 2,992,060

CORRECTION AND END-OF-LETTER MARKER FOR DICTATING MACHINE Filed Sept. 4,1956 m 30 W" I! IHHHHCI" "'W '52" Z4 '26 R.

INVENTOR Frederic/v Wfl/oerts 2 BY w United States Patent 2,992,060CORRECTION AFND END-OF-LE'I'IER MARKER FOR DICTATING MACHlNE FrederickW. Roberts, Fair-field, Conn, assignor to Dictaphone Corporation,Bridgeport, Conn., a corporation of New York Filed Sept. 4, 1956, Ser.No. 607,959 4 Claims. (Cl. 346-76) This invention relates to an improvedarrangement in a dictating machine for indicating the point on a recordof a correction or the end of a letter or the like on a paper slipassociated with the record.

An object of this invention is to provide an improved marking system ofthe above kind wherein the marking element itself is not consumed, i.e.is permanent, but yet gives a readily seen mark on a paper slip suppliedfor use with it.

Another object is to provide such a system which is trouble free, has along service life and which is inexpensive.

These and other objects will in part be understood from and in partpointed out in the description given hereinafter.

For convenience in transcribing a dictation record, it is desirable tohave some means of indicating corrections and/or end-of-letter points onthe record. In most dictating machines this is accomplished by means ofa marking system which provides a separate slip, tab or card of paper orthe like upon which the marks can be made, usually positioned adjacentthe record and traversed by a marking device as the recorder carriagetraverses the record.

In dictating machines using such a marking system, an important problemin the past has been how to make a mark of sutiicient clearness anddefinition. The use of pencil lead or of ink as the marking medium has,of course, been tried-but this presents the difficulty of having torenew the medium periodically. Human nature being what it is, thisnecessity to renew usually results in the non-use or non-usability ofthe marker and makes for an irritating inconvenience.

Alternatively, permanent markers, such as a brass stylus, have beentried but these usually gave too faint a mark to be satisfactory.Others, although they gave a clear mark, required very expensive orperishable slips, cards or the like. The present invention seeks toovercome these difficulties.

In accordance with this invention, a very efiicient and inexpensivemarking system for a dictating machine is provided. The marking elementincludes a simple and small size heating element carried on thedictating machine carriage in proximity to a pad of paper slips ofheat-sensitive material. By activating the heating element, a verydefinite and easily distinguishable mark is produced on the tab. Furtheraccording to the invention, an arrangement is provided for energizingthe heating element which is operable, either directly at the dictatingmachine or remotely to produce, for example, either of two differentmarks, one for corrections and the other for end-of-letter indications.This arrangement gives reliable operation and is quite inexpensive; inaddition since it can be controlled by the master switch of thedictating machine, accidental marks when the machine is not in use areprevented. The heat sensitive paper from which the paper slips, tabs orcards are made is commercially available at low cost and can be storedfor long periods without deteriorating. It is not easily markedmechanically as by scratches and the like, and therefore can standrelatively rough handling.

A better understanding of the invention together with a fullerappreciation of its many advantages will best be gained from a study ofthe following description given in connection with the accompanyingdrawings in which:

FIGURE 1 is a front view of a dictating machine fitted with aheat-operated marking arrangement according to the invention;

FIGURE 2 is a greatly enlarged side view of the heatmarking device andheat-sensitive slips, taken as indicated by lines 22 in FIGURE 1;

FIGURE 3 is a somewhat more enlarged perspective view of the heatingelement in the device of FIGURE 2; and

FIGURE 4 is a diagram of an electrical circuit embodying features of theinvention and adapted to selectively energize the heating element ofFIGURE 3 according to the invention.

A dictating machine, generally indicated at 10 in FIGURE 1, includes anendless belt record 12 adapted to be moved in the direction of arrow 14past a recording head 16. This head 16 is moved by a carriage laterallyand slowly in the direction of arrow 18 when record 12 rotates, therebytracing out a helical path or sound track on the belt record 12.

Mounted for lateral movement along with head 16 is a marker device 20which extends downward and rides in front of a pad 21 of paper indicatorslips 22. A mark made on a slip 22 by marker 20 corresponds to andindicates a correction or end-of-letter point on record 12. When theoperator of the dictating machine wishes to make such a mark hedepresses one end of a doubleended control lever 24, on the left end Cto make a correction indication or on the right end L to make anend-of-letter mark.

The enlarged side view of the marking device 20 shown in FIGURE 2includes a housing 26 mounted on a shaft 28 carried on the end of thearm 30 which in turn is supported from the movable carriage of recordinghead 16. Housing 26 is spring urged into the full line position shownbut can be swung back to the dotted line position to permit, forexample, the removal of a marked slip 22 from the pad 21.

Spring mounted within housing 26 is an insulating block 32 whose frontface is lightly pressed against the top slip 22 of the pad 21. Block 32is carried by an arm 34 which is pivoted to housing 26 at 36 and whichalso carries a finger plate 38 by which the block and housing can beretracted to their dotted line positions when desired.

Referring to FIGURE 3, the insulating block 32 has recessed in its frontface two heater wires 40 and 42 which are adapted to be heatedselectively by an electric current thereby to put a mark as desired onthe top slip 22 of the pad 21 as shown in FIGURES 1 and 2. Wire 40 isconnected between lead 44 and lead 46, and wire 42 between lead '46 and48.

Referring to FIGURE 4 wherein heater wires 40 and 42 are representedschematically by resistor symbols, lead 46, which is common to both ofthe heater wires, is connected to one side of an alternating voltagesupply 50. The other side of this supply runs to a master power switch52 for machine 10. When this switch is closed, current flows through arectifier 54 and through each of two resistors 56 and 58 to charge twocapacitors 60 and 62, respectively. By pressing the L or the C switch,both normally-open and operated selectively to closed position by thedouble-ended control lever 24 seen in FIGURE 1, heater wire 40, or 42,is energized thereby to make a mark on the heat sensitive slip 22.

Resistors 56 and 58 are advantageously chosen so that, if switch L or Cis held down for longer than it takes to discharge capacitor 60, or 62,the current which can flow through wire 40, or 42, is too small toeffect substantial heating of the wire. Thus each mark produced on aslip 22 will have the same quality as every other mark so long as switchL, or C, is completely closed for the short time necessary to dischargecapacitor 60, or 62, through its heater wire.

Capacitor 60 and 62 can be different in size and, if so, the dischargeof one into its respective resistance Wire 40, or 42, will produce amark on a slip 22 different from the mark produced by the otherresistance Wire and its capacitor. If desired, a single capacitor can beused to energize, through the two switches L and C, both of the wires 40and 42. Alternatively, a single heater wire can be used with twocapacitors to produce'two marks of different intensity.

The invention has been tested using slips 22 made of various types ofheat-sensitive material. Similar heat sensitive paper is now on themarket being sold under the trademark Thermo-Fax. In these testsverysatisfactory results were obtained using the ordinary powerline supplyvoltage of about 115 volts, and condensers-of about microfarads capacityeach.

The above description is intended in illustration and not in limitationof the inventionv Various minor changes and modifications in theapparatus illustrated may occur to those skilled in the art and thesemay be made without departing from the spirit or scope of the inventionas set forth.

I claim:

1. In a recording machine of the character described, a pad of slips ofheat-sensitive visual indicating material mounted on the machine, a heatmarking means includ ing a resistance element adapted to traverse saidslips in close proximity thereto in accordance with the position of arecording head relative to a dictation record and the like in saidmachine, and means to selectively energize said marking means to producevisible marks of uniform quality on the top one only of said slips, saidmeans to energize including a capacitor, a source of direct voltage, aresistor connecting said source to said capacitor, and a manuallyoperable switch in series with said resistance element andsaidcapacitor, said resistor being large enough to prevent effective heatingof said heat marking means after said capacitor has been discharged evenon prolonged actuation of said switch, said capacitor being large enoughto produce a visible mark on said slip without burning it.

2. The combination of elements as in claim 1 in which said resistanceelement includes a first heating wire and a second heating wire spacedtherefrom, said wires being adapted to produce marks at laterally spacedpoints on said top slip, each of said heating wires being energized by arespective capacitor and a respective manually operable switch, each ofsaid capacitors being charged from said source.

3. The combination of elements as in claim 2 in which each of saidwi-res includes a single resistance wire filament mounted in a frontface of a heat-insulating block, said filaments lying along a straightline which is generally transverse to the direction of travel of saidheat marking means relative to said slip, said filaments being recessedslightly into the front face of said block, said block being resilientlyurged lightly into contact with the surface of said slip.

4. The combination of elements as in claim 2 in which said capacitorsare connected to said source of voltage in series with themain powerswitch of said machine.

References Cited in the file of this patent UNITED STATES PATENTS1,245,588 Hib-bard Nov. 6, 1917 2,292,736 Betz Aug. 11, 1942 2,539,874Stockfleth Jan. 30, 1951 2,644,738 Gardner July 7, 1953 2,820,639Gillette et al. Jan. 21, 1958 FOREIGN PATENTS 904,381 France Nov. 5,1945

